Carburetor



May 17 i927. E. FERQLD! gw GARBUETOR Filed July 1, 1922 2 sheets-Sheet 1 May W, w27., 1,5221@ E. FEROLDI GARBURETOR Filed July 1, 1922 2 sheets-sheet 2 l caf) l 2 I9 Fm. 5

Z6 ad v s 30" Bf l I 30 so" L 1 |37 I Y? l2 l -psection on line 1--1 of Figure 2; Figu 425 of Figure 2,; Figure 4 is a sectional PatenteuMay. 17, 1927.

anarco 'nanou-a1, or. '.rUnIN, ITALY.

PATENT FoFF'ICE.

caanunnroa.

Application filed July 1, 1.922, Serial No'. 572,144, and in France 8, 1921.

The present invention relatesto carburct-- as.

Drs for 'fuels heavier than petrol, such parain, naptha, benzol and the like, which are provided with .means for an auxiliary4 '5` supply of lightfuel.'A

The present provided for causing the sup ly ofthelight and heavy fuels, as wellV ast atl of water if m desired,v to depend upon 'the .heating ofthe carburetor, this heating vbein V"by itself known inthe carburetors for heavy fuels. The fuel Suppl is thus automatically controlled by the iieating imparted to. the carburetors and -hence is controlled by the running-of the engine.

In the. accompanying drawings isA shown by-way of example a construction of a car,- buretor according to this invention, with a vertical carburetlng chamber.

In said drawings :-Figure 1 is a` vertical 1; Figure 3 is a vertical section on line 3-#3 plan of the carburetors, taken onbroken sectlon line v4 4 of Fig. 1. lFigure 5 is a fragmentary sectional viewto an enlargedscale showing a modified'fuel nozzle and the .parts adja- 3o cent thereto. I In the construction illustrated,` the arburetor compri-ses a body 1 provided wit a float chamber 2 and including acarburetmg chamber 3; in alignment with this chamber 36 is mounted a sleeve 4 adapted for connection with the engine suction duct (not shown on the drawing), and provided with inwardly rejecting e integral with the-carburetor bodyA 1.

4o In the walls of the body 1 and ofthe sleeve 4 are provided spaces 6 communicating with each other, and in which circulate the exhaust gases of thev engine or other warm fluid which is admitted and discharged -through .branches' ands.`

.The several spaces. 6 are connected by a conduit .9, throu h which conduit the fluid is thus circulate In the example illustrated the working of the carburetor isregulated by means of a j cock 10-mounted transversely in the' car-- bureting chamber 4 and` seated in two opposite recesses 31 having cylindrical surfaces,

said'cock bei g operated from the outside by 56 means of a l ver 11.

The cock plug has a hollow 10 intowhich invention has for its .object a carburetor of. this kind'in which means are 16' securedtothe walls as shown.v

ribs .5. This sleeveA 4 could also the fuel is projected in lthe axial directionby a sprayer 12, and two opposite slots 13 yand 13. vthe former'one for the passa e of the air into the hollow of the plug, an the second for the escape of the mixture which 1s formed in the said hollow, when the cock 1s open. For supplying theengine when running at slow speed, the c'ock plug 10 is further provided with a radial `hole 14 which, when the cock is in the closed .position vas shown on the drawing, registers witha 'recess' 15 (Figure'l) so as to establish communication between -the chamber ofthe cock andthe carburetingchamber, at' theside connected to the suction duct of the engine. -In the body 1 of t carburetor, referably close toone ofth heated cham ers 6, is provided-a well'16 which communicates at its lower end with the float chamber 2, vand at the top terminates in the interior of the ,sprayer 12 through throttled ports, for instance by means of a groove 17 outside of the sprayer, and `radial holes 18. This well has a relatively small cross-section and va very large surface,.and this may be obtained for instance by providing a screw thread on the inner wall of the well itself or by arranging in the same a helically wound wire vIn'the body 1 ofthe carburetor is=further provided a conduitA 19 communicating with the atmosphere, for instance through a regu'- la'ting plug 2() ,'(Figure 2) and opening at the rear end ofthe sprayer 12.

During the usual running of the engine l lthe heavy fuely contained in the receptacle 2 is heated in the well 16 to such an vextent as to ensure an `easyjlow of said fuel.: The fuel therefore arrives at the sprayer 12 in such conditions that it is completely atom- ,ized .by the axial jet of air which passes into it after strongly.` heated through the conduit 19.

The suction of fuel depends'on the de- Apression produced by the engine in the sprayer `12, so 'that it changes in proportion to the different speeds of ,running of the engine y i i a mmunication 'between the well 16 -and the sprayer 12 is established through throt-` tled openings, and the are so rev lateds to allow the passage o the uantity of fuel required for the. normal Spee andthere'fore 110 at a'speed which corresponds tothe desired. degree of heating.v

los"

I automatically reduced. In fact, as the supply of fuel is reduced, its heating becomes stronger in the well 16 and there 1s generation'of vapours, and the latter produce a back pressure, the effect being to reduce the,

admission of fuel to the sprayer 12. At the lowest speed (whenrunning dead slow) the supply of fuel is limited to the said vapours which make it possibleto form, a good mixture. v

ln order to heat also the main air supply. reaching the carbureting chamber, the heat-- ed zone of the intake 3 is .providedwith 'holes 2l, and in the chamber `6 are arranged tubes 22 establishing communication between the chamber 3 and the atmosphere so that the air drawn in through said holes-and tubes, is submitted to a preliminary heating.

Moreover there are provided small holes 23 establishing communication between the chambers 6 and the carbureting chamber .3, and through the said holes into the said chamber passes a small portion-oit` the hot gases, the eHect of which is to heat considerably the air intended to form the final mixture.

If a hot fluid other than the exhaust gases of the engine circulates in the .chamber r6, the holes 23 will be dispensed with, orthey may establish communication between the carbureting chamber and a separate conduit into which arcadmitted the exhaust gases of the engine.

In order to heat also the air which is added to the mixture during the running at slow speed, opposite the conduit 14 is provided in the cock 10 another conduitv 24 which comes opposite a small tube 25 -opening into the intake 3 and mountedin one of the chambers 6 where it is surrounded by the hot. circulating gases.

Itis known that in carburetors of this type a supply of water isfre'quently used. For this supply when such is rovided, the body 1 is provlded with a con uit 26 which may be -connected byvmeans ofa union 27 and a hollow screwthreaded plug 28, to a rece tacle containing water.

he conduit 26 is constitutedby walls provided in one of the chambers 6 in which circulates a hot fluid, l so as to be strongly heated, and the said conduit communicates with the chamber 3 through a small hole 29 opening below the cock 10.

Also in this case, as in the case of the fuel supply, the cross-sectional area of assages for the water is regulated in suc a manner that. at the'normal speed of run- Aning, the water passes through the conduit 26 with a speed corresponding to the desired heating.v

Consequently when the suction decreases at the lowest speeds, the water remains for When the cockis opened b magere alonger timevin the conduit 26 and being heated more strongly, it generates steam which interrupts or stops altogether the supply of water.V In this way, admission of water into the carbureting chamber when its presence is not desi-red, is automatically avoided.

To ensure the formationof a combustible mixture when starting the engi'ne, the carburetor as is well known, must be provided with an auxiliary feed for light fuel, generally petrol.

According to this invention, this auxiliary feed igure 1) comprises a tube 3() coming from a'tank (not shown) which is at a higher level than the 'sprayer 12 and opening int-o the groove 17 which communicates with the sprayer 12.

When the/"engine is running at low speed i When the carburetor body is heated, however, the heavy fuel flows easil and reaches groove 17 and passages 18, w ile the light fuel, as a result-of the heating imparted to it while itis flowing along passage 30, forms bubbles of vapor which restrict the arrival of further amounts of light fuel in the groove 17. Y

Such a working which contributes .to ensuring automatically the exclusion of the light fuel as soon as the engine runs at normal speed, may be^ assisted by providing for the4 light fuel a small well 1n communication with the tube 30 and the groove 17, the .walls of the said well being strongly heated. In the vcase of Figure 5 the atomization vof the fuel is improved by the fact that the air enters the nozzle through holes 19 provided inthe nozzle 12 at the rear of the passage 18 for the supply of the fuel therein; the passage of the air throu h said hole 19 may be adjusted at will y-the screw -19".

With the cock 10 in the osition shown in Figure 3, the engine wor s at theminimum speed, and its suction acts in the interior of the cock 10 through the hole 14 by drawing into it air and fuel through the sprayer 12 and additional air through the tube 25.

turning itin the direction of the arrow4 Fi re 3) the suction acts onthe slot 13 an air passes from the mouth 3 through the slot 13 into the hollow in the cock .plu 10, which air is heated b well as by the direct action of the hot gases escapmg from the holes23. If there is a contactwith t e hot walls as water supply, the said water escapes through the hole 29 in proportion to the suction.`

Attention is called to my applications Serial Nos. 341,350 and 477,469 in respect of the features shown on the annexed drawings but not claimed per se as forming the subject matter of said other patents and patent applications. 4

What I claim as my invention and desire to secure by United States Letters Patent 1s:-

A carburetor for internal combustion engines adapted to operate on heavy fuel, comprising la carbureting chamber, separate means for containing a heavy fuel and a llght fuel, separate ducts connecting said means with said chamber, said ducts having restricted portions so as to prevent the pas` sage of the heavy fuel When the carburetor is cold and to prevent the passage of the light fuel when the carburetor is heated by restricting the flow of vapor, and means for heating said carburetor by a fluid the temperature" of which depends upon the operation of the engine to control the flow of thev two fuels to the carbureting chamber.

In testimony whereof, I have signed vml name to this specification.

ENRICO FEROLDI. 

